1. Technical Field
The present disclosure relates to a method of driving a lamp, a lamp driving apparatus for performing the method of driving the lamp, and a liquid crystal display device having the lamp driving apparatus. More particularly, the present disclosure relates to a method of driving a lamp for variably adjusting a driving duty cycle of the lamp and adjusting a supply voltage according to an image change rate, a lamp driving apparatus for performing the method of driving the lamp, and a liquid crystal display device having the lamp driving apparatus.
2. Discussion of the Related Art
Generally, a liquid crystal display (“LCD”) device displays an image thereon by adjusting a transmission of light through the liquid crystal, according to image information that is provided from an external device. In order to display the image, an LCD panel of the LCD device includes liquid crystal cells arranged in a matrix and a switching element, such as a thin-film transistor (“TFT”), for switching the image information that corresponds to each of the liquid crystal cells.
A driving apparatus of the LCD panel controls the switching elements to provide each of the liquid crystal cells with the image information. Further, the driving apparatus of the LCD panel suppresses deterioration of the image induced by blinking, afterimages, etc. Additionally, the driving apparatus of the LCD panel controls the LCD panel so that the image information includes a positive polarity or a negative polarity for a predetermined voltage level, so as to decrease a driving voltage of the LCD panel.
As display technology becomes more developed, technology for displaying moving images is increasingly more in demand, in addition to the technology for displaying still images. The technology for displaying moving images, however, is somewhat difficult to implement in the LCD device, because a response speed of the liquid crystal is slower than a one-frame period, that is, a time period corresponding to one frame, when a new voltage is supplied to the liquid crystal at the following frame after maintaining a voltage, for example, an image signal or a data voltage, charged in the liquid crystal during the one frame period, motion blur is generated.
To remove the motion blur, the LCD device controls an operation of turning a lamp on and off, in response to a display speed of the image and a display phase of the image.
When the lamp is turned off, however, a luminance may be decreased. Therefore, in order to solve the decrease in luminance of the LCD device, a current supplied to the lamp is increased when the lamp is turned on. More specifically, when the lamp is turned on and off, in response to the display speed and display phase of the image, the motion blur is removed. Accordingly, the image is cleanly displayed on the LCD device, but the luminance may be decreased when the lamp is turned off.